The obvious one is to create zone (zones rounded by road) and sell them for industry/residential/commercial purpose. Those zones attract people you have to build more zones for.
The more people, the more traffic congestion, the more road needed, etc..
It's called Sim City, no need to type so many words, "like SimCity" is enough
Generally there are 3 routes:
1) build zones/buildings and roads (SimCity)
2) manage traffic only (TrafficGiant/Cities In Motion)
3) manage traffic and build roads but no buildings/zones (so something between these two) (Transport Tycoon)
Personally, I would want to play model 2) since Paradox messed up with CiM and made it all about traffic jams (which is not that fun). I would love to play a game that is fixed CiM. I also recommend avoid 1) it's the most overused (sub)genre (no surprice, since SimCity is so ancient). As for 3), I don't know, there is the open source OpenTTD which is cing of extremely advanced, plus I don't find it that amusing for some reason.
All above written only taking my personal taste as a player into account